Liquid laundry detergent compositions with low equilibrium relative humidities have the advantage of being less susceptible to microbial contamination. There is also a trend towards so called compacted liquids that minimise the presence of unnecessary ‘filler’ liquids such as water. Such compositions are more environmentally friendly as less unnecessary material needs to be transported, so reducing the environmental impact of such transport operations.
However, such compacted composition can often have high viscosities due to the high relative concentration of the cleaning materials such as anionic surfactants. Traditionally, hydroxyl-containing amines have been used in such compositions to ensure consumer acceptable viscosity of the liquid laundry detergent composition. Also, acceptable viscosity is required to allow processability of the composition during manufacture. The hydroxyl-containing amines are often used as neutralising agents for the anionic detergent surfactants such as linear alkylbenzene sulphonate.
However, there is now a desire to reduce the overall level of such hydroxyl-containing amines.
Reduction in the level of the hydroxyl-containing amines of known low relative humidity laundry detergent compositions can result in high viscosity of the composition which negatively impacts the ability of the consumer to accurately pour and dose the composition. Also, processability of the composition is impacted as it is difficult to handle such viscous compositions during manufacture.
Thus, there is a need in the art for low relative humidity liquid laundry detergent compositions containing lower levels of hydroxyl-containing amine compounds, but which exhibit consumer acceptable and/or process acceptable viscosities.
It has been surprisingly found that the above problems are overcome by the specific formulation space of the present invention. The formulation space described below can provide a liquid composition having a low relative humidity and comprising lower levels of hydroxyl-containing amine compounds but which has acceptable viscosity.